Filter For Rainwater Harvesting

ABSTRACT

A strainer for a rainwater catchment system includes a container having a top end and a lid sized to cover the top end. The lid has an opening formed therein defined by an edge. The strainer further comprises an upper flange extending outwardly, a vertical side wall extending downwardly from the upper flange, and a bottom rim connected to the side wall, with the bottom rim extending inwardly. A filter removably connects to the bottom rim, with the filter including a lower reinforcing web, an upper retainer, and a mesh held between the lower reinforcing web and the upper retainer, so that the filter is adapted to allow rainwater to pass therethrough while filtering debris therefrom.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part application of U.S. patentapplication Ser. No. 12/847,413, filed Jul. 30, 2010, the disclosure ofwhich is incorporated by reference herein in its entirety.

THE INVENTION

This invention provides a means for filtering rainwater before it entersthe rain barrel. This invention allows the user to customize thefiltration media based on their need. Typically, this invention providesa simple inexpensive solution for adapting a variety of food-gradeplastic drums to become a rain barrels.

The design of the basket, includes a wide flange rim at the top, whichallows it to adapt to many different types of containers for rainwaterharvesting. The bottom of the basket has holes that allows forinterchangeability. A simple hardware kit enables a range of differentfilter meshes and strainer panels to be quickly changed out of thebasket.

The strainer basket has been sized to easily fit onto the top of a largeplastic drum, which is part of adapting the typical 55-gallon drum tobecome a rain barrel. The size of the basket is small enough to fitbetween the bungholes of a 55-gallon drum, or the retainer ring of abulk olive barrel. The basket's wide brim fits snugly to the lid of thebarrel, thus preventing debris and insects from entering the collectionvessel.

A grade of mesh, which is mosquito-proof, is inserted into the bottom ofthe basket, along with the rigid strainer panel, which protects the finemesh from debris that may wash down from the gutter. The mosquito-proofmesh prevents mosquitos from entering the barrel. The mesh is so fine italso prevents mosquito eggs from being washed into the collectionvessel, from the gutter above.

The rigid strainer panel reinforces the basket's strength and providesadditional structure to handle heavy water flows. The finer mesh enablesthe water to flow more smoothly into the vessel, while keeping finerdebris out of the barrel.

Multiple layers of mesh and strainer panels can be coupled together tocreate a more sophisticated filtering device, which can employ sand,and/or granular activated carbon.

Methodology for Making the Components

The strainer basket is a combination of molded and flat plastic parts.The basket can be made in a variety of methodologies, based on thequantity needed: injection molding for runs of 10,000 or more,thermo-forming for runs of 10,000 or less, and 3D printing for less than100 at a time.

A variety of plastics are appropriate for this product such aspolypropylene, which holds up well in exterior conditions.

The various mesh filters are made of extruded polypropylene and areseparate pieces, so they can be interchangeable. The extruded plasticmesh is a readily available commodity manufactured in large quantities.For this product, the desired mesh filters would be die-cut frompre-existing product.

The hardware kit, would be polypropylene nuts and bolts.

DRAWING FIGURES

FIG. 1

Top view of the strainer basket

FIG. 2

Side view of the strainer basket

FIG. 3

Exploded view of strainer basket assembly

FIG. 4

Top view of strainer basket nested into 55-gallon plastic drum lid

FIG. 5

Section view of strainer basket nested into plastic 55-gallon drum atdownspout

FIG. 6

Section view of strainer basket adapted with sand/GAC filtration media

REFERENCE NUMERALS

20 Wide Flange of strainer basket

22 Mesh on top of rigid strainer panel

24 Mesh over open holes of rigid strainer panel

26 Bolt for hardware assembly

28 Retainer ring

30 Side of strainer basket

32 Bolt

34 Hole for bolt/nut hardware assembly

36 Retainer ring

38 Mesh

40 Opening within rigid strainer panel

42 Rigid strainer panel

44 Wide flange of strainer basket

46 Opening at bottom of strainer basket

48 Nut for hardware assembly

50 Strainer basket

52 Food grade plastic drum converted to rain barrel

54 Downspout

56 Strainer basket

58 Rain barrel

60 Strainer basket

62 Mesh layers

64 Rigid strainer panel layers

66 Sand or GAC filtration media

Operation

The strainer basket is placed within the lid of a barrel outfitted forrainwater harvesting. The basket is secured to the lid with Velcrostrips or hardware. Either option keeps the basket securely affixed tothe lid of the barrel, yet enables the basket to be removed whennecessary. The basket can easily be lifted out of the barrel lid,cleaned, and if necessary the mesh can be replaced.

The downspout, leading from the rain gutter is then set at aperpendicular angle, with an elbow fitting into the basket. When itrains, water flows off the roof, into the gutter and through thedownspout into the strainer basket, which filters the water prior todraining into the barrel.

The rainwater, which may be washing down leaves, twigs, and otherdebris, is filtered through the mesh sections of the strainer. Thebasket bottom is reinforced with the rigid strainer panel, whichstrengthens the basket and helps prevent ruptures in the mesh screening.As the rainwater pours into the basket, the mesh bottom of the strainerbasket diffuses the water, minimizing splash back.

The strainer basket is fitted with a fine mesh, capable of preventingmosquito eggs being washed into the rain barrel. The mesh is also fineenough to prevent flying mosquitos from entering the collection vessel.

Depending on local conditions and the desired water quality, even finermesh, than mosquito-grade mesh, can be used. Additionally, a layer ofsand or granular activated carbon (GAC) can be sandwiched into thebottom of the strainer basket with an additional layer of mesh and anadditional rigid strainer panel, for finer filtration.

Benefits

The benefits of this design are numerous. The flexibility and modularityof the design, enable the user to customize the filter for theirspecific need.

All the parts are replaceable. If the mesh wears out, the whole basketdoes not have to be replaced, just the mesh has to be replaced.

The simplicity of how the components fit together make it possible forquick assembly in the field. The user does not need any power tools toassemble the water filter.

The parts are very light weight and nest together saving space andminimizing shipping costs.

The design of the strainer basket keeps mosquitoes out of the collectedrainwater. Many rain barrels do not have mosquito protection and rely onthe user having to add chemicals to kill mosquito eggs.

The depth of the strainer basket, allows water to pool, while it isbeing strained, which ensures the maximum amount of water is captured.Many rain barrels do not provide a collection chamber, so that during aheavy downpour, much of the water runs off before it can be captured.

The strainer basket screens out debris like dead leaves, twigs andaggregate from deteriorating asphalt shingles. Because the basket is soeasy to remove, it is easy to clean. Most rain barrels, do not providean easy way to screen debris, much less provide a cleanable andreplaceable filter. Keeping the water cleaner as it goes into the barrelmakes it easier to keep the barrel clean.

SUMMARY

This invention has the will help people collect and filter rainwater asa supplemental source of water primarily for garden uses.

1. A strainer for a rainwater catchment system including a containerhaving a top end and a lid sized to cover the top end, the lid having anopening formed therein defined by an edge, the strainer comprising: anupper flange extending outwardly; a vertical side wall extendingdownwardly from the upper flange; a bottom rim connected to the sidewall, the bottom rim extending inwardly; and a filter removablyconnected to the bottom rim, the filter including a lower reinforcingweb, an upper retainer, and a mesh held between the lower reinforcingweb and the upper retainer, the filter adapted to allow the passagetherethrough of rainwater while filtering debris therefrom.
 2. Thestrainer of claim 1 wherein the flange, the side wall, and the bottomrim are integrally formed.
 3. The strainer of claim 2 wherein theopening in the strainer is circular in shape.
 4. The strainer of claim 3wherein the filter further comprises: the lower reinforcing web, theupper retainer, and the mesh being circular in shape.
 5. The strainer ofclaim 4 wherein the filter further comprises: the lower reinforcing web,the upper retainer, and the mesh having substantively the same outerdiameter and also being alignable so as to permit simultaneous removableconnection to the bottom rim.
 6. The strainer of claim 5 wherein thelower reinforcing web, the upper retainer, and the mesh have at leastthree sets of vertically aligned holes, and further comprising: athreaded bolt extended through each of the sets of the aligned holes,with a corresponding nut secured thereto, thereby to form the removableconnection.
 7. A strainer for a rainwater catchment system including acontainer having a top end and a lid sized to cover the top end, the lidhaving an opening formed therein defined by an edge, the strainercomprising: an upper flange extending outwardly; a vertical side wallextending downwardly from the upper flange; a bottom rim connected tothe side wall, the bottom rim extending inwardly; and a filter removablyconnected to the bottom rim, the filter comprising a water permeableupper layer, a water permeable lower layer, and a layer of filtrationmedia held sandwiched therebetween.
 8. The strainer of claim 7 whereineach of the upper and lower layers further comprises: a mesh and apanel.
 9. The strainer of claim 7 wherein the layer of filtration mediacomprises at least one of sand and granular activated carbon.
 10. Arainwater catchment system comprising: a container having a top end; alid sized to cover the top end, the lid having an opening formed thereindefined by an edge; and a strainer further comprising: an upper flange;a vertical side wall; a reinforcing web; and a mesh coupled to thereinforcing web; wherein the strainer is removably held by the lid overthe opening, and sized and shaped to accommodate the edge of the lidthat defines the opening, wherein the mesh is located below the opening,the mesh adapted to allow the passage therethrough of rainwater and tofilter debris from the rainwater when the container is located such thatthe opening is in the flow path of a rainwater downspout.
 11. Therainwater catchment system of claim 10 wherein the flange, the sidewall, and the reinforcing web are integrally formed.
 12. The rainwatercatchment system of claim 10 wherein the mesh is heat-sealed to at leastone of the upper and the lower surfaces of the reinforcing web.
 13. Therainwater catchment system of claim 10 wherein the opening and thestrainer are circular in shape, and the opening is offset with respectto a center vertical axis of the container.
 14. The rainwater catchmentsystem of claim 10 wherein the opening is circular in shape, and theflange is also circular in shape and sized to extend over the edge ofthe opening about its entire periphery.
 15. The rainwater catchmentsystem of claim 10 wherein the reinforcing web includes radiallydirected spokes.
 16. The rainwater catchment system of claim 15 whereinthe radially directed spokes are curved and define a flower petal shape.17. A rainwater catchment system for catching rainwater from a downspoutand collecting the caught rainwater in a container, comprising: astrainer sized to be removably held within an opening at a top end ofthe container, the strainer further including: an upper flange sized andshaped so as to engage the container at the top end; a side walldepending downwardly from the flange; a mesh held by the side wall at abottom end thereof, the mesh located at a vertical level below theflange; and a reinforcing web secured to the mesh and defining thebottom of the strainer.
 18. The rainwater catchment system of claim 17wherein the flange, the side wall, and the reinforcing web areintegrally formed and the mesh is heat-sealed to either the upper or thelower surface of the reinforcing web.
 19. The rainwater catchment systemof claim 17 wherein the strainer is circular in horizontal crosssectional shape.
 20. The rainwater catchment system of claim 17 whereinthe reinforcing web includes radially directed spokes.
 21. The rainwatercatchment system of claim 19 wherein the radially directed spokes arecurved and define a flower petal shape.
 22. The rainwater catchmentsystem of claim 17 wherein the mesh has a mesh size of 400 microns. 23.The rainwater catchment system of claim 10 wherein the container is oneof the following: a conventional 55-gallon plastic drum and a 35-gallonmetal trashcan.